Rotatable pipe coupling

ABSTRACT

A plastic &#39;&#39;&#39;&#39;tee&#39;&#39;&#39;&#39; coupling for toilet and sink systems of mobile homes and the like. The coupling has a main tube with an integral flange and side tube. The coupling also has plastic platic collar that snaps on over the flange and is permanently retained between the flange and side tube. The plastic collar has sufficient &#39;&#39;&#39;&#39;give&#39;&#39;&#39;&#39; to springedly hold a rubber sealing gasket between a connecting pipe member and a sliding seal surface of the main tube. The sliding seal surface and the gasket form a sliding liquid tight seal that can be rotated 360* to angularly align and connect the side tube with another pipe.

United States Patent 1191 Stein 1 1 Oct.2, 1973 [73] Assignee: AnondaPlastics, Inc., Pacoima,

Calif.

{22] Filed: Apr. 26, 1971 [21] Appl. No.: 137,470

1521 u.s.c1 251/148, 138/89, 285/31, 285/151, 285/156, 285/184. 285/363,

285/DIG. 2, 285/DIG. 22

1511 1111. C1. F16] 27/00, F16k 51/00 [58] Field of Search 2215/31, 32,151, 215/152, 414, 415, DIG. 22, 184, DIG. 2,

1,053,528 2/1913 Mueller et al. 285/31 1,186,325 6/1916 Metzger 285/415X FOREIGN PATENTS OR APPLICATIONS 614,513 2/1961 Canada 285/156 464,62312/1968 Switzerlandm" 285/DIG. 22 586,881 12/1958 Italy 285/156 PrimaryExaminerThomas F. Callaghan Att0rney-Larry N. Barger [57] ABSTRACT Aplastic tee" coupling for toilet and sink systems of mobile homes andthe like. The coupling has a main tube with an integral flange and sidetube. The coupling also has plastic platic collar that snaps on over theflange and is permanently retained between the flange and side tube. Theplastic collar has sufficient give" to springedly hold a rubber sealinggasket between a connecting pipe member and a sliding seal surface ofthe main tube. The sliding seal surface and the gasket form a slidingliquid tight seal that can be rotated 360 to angularly align and connectthe side tube with another pipe.

21 Claims, 10 Drawing Figures PATENTEDUCI 2191s SHEET 1 BF 4 INVENTOR-WILLIAM H. ST BY 7'. Z A ORA/EV SHEET 2 OF 4 PATENTEDUCT 2191a INVENTOR.

.WILLIAM H. STE N J V ZTOR NE y PATENTEnncr 2197s SHEET 30F 4 INVENTORW1 LL I A M H. 9/ BY 5 STE/1v W M w EA/Ev SHEET t [1F 4 #76. 7 I I WINVENTOR. WILL IAM H STE/IV ORA/E Y aorarksrs rrre eourtruc BACKGROUNDIn recent years the mobile home and recreation vehicle industries havebecome very large, and many of these homes and vehicles have plumbingfacilities such as toilet, sink, shower, etc. The toilet dischargeshuman waste which must be collected in a holding tank and carried withthe vehicle until it can be emptied into an approved reservoir. Thereason for the holding tank is to avoid the order and health problems ofthe human waste. Many gasoline filling stations have dumping reservoirsspecifically for emptying these holding tanks.

Drain water from the sink and shower is not required to be kept in aholding tank. It is sometimes drained onto a lawn or down a street drainor directly onto the ground when vacationing in the woods. Since waterfrom the sink and shower are handled differently from the toilet sewage,many mobile homes and recreation vehicles are equiped with a sanitarytee coupling. The sanitary tee has a main tube connected to a slide gatevalve at an outlet of the holding tank. A branch or side tube enters thetee coupling downstream of the slide gate valve and this side tube isconnected to the drain pipe from the sink, shower or other fixture thatdoes not discharge human waste. With this arrangement the drain watercan be drained out without opening the slide gate valve on the holdingtank.

In the ast these sanitary tee couplings have had many problems. Perhapsone of the most serious problems was the tee coupling that did not fitproperly when installed on a newly built mobile home or recreationvehicle. Some of the previous sanitary tee couplings had a series offixed holes in an integral flange on the coupling. In theory, if theflange had eight equally spaced holes in its flange, the side tube couldbe positioned at 45 intervals depending on how the flange holes weremated with holes in a similar connecting flange. The side tube was thensuppose to be properly aligned with a drain pipe from a shower or sink.In practice this alignment often did not occur. Adding to the problemwas the lack of standardization of plumbing design of the many differentmanufacturers of mobile homes and recreation vehicles. Somemanufacturers brought their pipes in nearly horizontal, others nearlyvertical, and others at a multitude of angles. If the side tube of thesanitary tee did not fit the workers installing it would force it intosufficient alignment for connecting. This would put a tremendous strainon the coupling causing it to leak at its joints when the customer tookthe vehicle and used its various plumbing facilities.

SUMMARY OF THE INVENTION I have overcome these disadvantages of previoussanitary tee couplings by providing a sanitary tee coupling that rotatesthrough 360 to position the side tube at any desired angle. Athermoplastic spring collar snaps over a flange on a main tube of thecoupling and urges a sliding seal surface of the coupling against agasket so that the coupling can be rotated manually after the flange hasbeen bolted in place. The main tube can have two or more side tubes ifdesired to create multiple tee couplings such as a double sanitary tee."The coupling can also have two spring collars and provide a very usefulrepair kit" that can be spliced into an existing thermoplastic pipeline.

THE DRAWlNGS FIG. l is a side view of the rotatable pipe couplingconnected to a slide gate valve at its right end and having a removablecap on its left end;

FIG. 2 is a left end view of FIG. ll showing how the main tube of thecoupling rotates to angularly position the side tube;

FIG. 3 is an enlarged sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is a front view of the thermoplastic collar that snaps over aflange of the main tube;

FIG. 5 is a side view of a thermoplastic pipe showing how it is cut tosplice in a repair kit of a rotatable tee coupling;

FIG. 6 shows the rotatable tee coupling assembled to the pipe of FIG. 55

FIG. 7 is a view taken along line 7-7 of FIG. 6, showing how the pipecoupling rotates to position the side tube;

FIG. 8 is an enlarged sectional view of the right end portion of therotatable coupling of FIG. 6;

FIG. 9 is a side view of a double tee coupling; and

FIG. 10 is a right end view of the coupling of FIG. 9.

DETAILED DESCRIPTION Referring now in detail to the drawings, FIG. 1shows the rotatable pipe coupling which includes a main tube 1 and aside tube 2 which are integrally molded as a unit from thermoplastic.The side tube has an outer sleeve section 3 adapted to be cemented orotherwise bonded to a connecting pipe wuch as a drain pipe from a showeror sink in a mobile home or recreation vehi cle. At the left end of themain tube is a removable cap 4 which has a series of latches 5 and 6that hook around and engage posts 7 and 8 on the main tube. To hold thecap near the coupling and not get lost when the cap is removed aflexible tie line 9 has ends that are connected to bottons 10 and 11respectively.

The right end of the rotatable coupling is firmly bolted to a slide gatevalve 40 by bolts 12, 13, 14, and as shown. Even when firmly bolted inthis manner, the main tube can be manually rotated to angularly positionthe side tube 2. This is perhaps best illustrated in FIG. 2 where thevertical side tube 2 is shown shifted to the right in the dotted linedrawing.

In FIG. 3, an enlarged sectional view shows the integral retentionflange 116 with a beveled outer surface and a sliding seal surface 17that encircles the main tube-s longitudinal passage. A thermoplasticspring collar 18 in the form of a thin plate has a circular opening witha beveled inner surface 19. The collar is molded as a continuousuninterrupted annular outer portion surrounding this central opening.With this configuration, the spring collar can be snapped over theflange 16 from the right end of the main tube 1 before the coupling isconnected to the slide gate valve. Once snapped over this flange thespring collar is permanently retained between the flange and the sidetube 2. Because of the outward protuberance in the form of the side tubethe collar 18 can not be telescoped over the left end of the main tubeand positioned against flange 16.

As shown in FIG. 3 the bolt can be tightened firmly against body 20 ofthe valve and the thin spring collar has sufficient give so it urges thesliding seal surface 17 against a resilient rubber gasket 21 to form asliding liquid tight seal with the gasket. Preferably the slidingsurface on the main tube engages one of the ribs 22 and 23 on thegasket. These ribs have triangular cross sections and extend annularlyabout the main tube to reduce friction and make an improved sea] at themain tubes sliding seal surface when the main tube is rotated. Thissealing gasket also has an inner web portion that extends inwardly intoa central passage of the sliding gate valve to form a seal with asliding gate 24 of the valve. There is also a similar gasket 25 on theopposite side of the gate 24 which is clamped between the valve body 20and adjacent pipe flange 26.

The spring collar 18 with its beveled surface is shown in FIG. 4 beforeit is snapped over the flange 16.

In the foregoing description I have described a sanit'ary tee couplingconnected to a sliding gate valve and having an end cap. By including aflange and spring collar on the main tube on opposite sides of the sidetube and the main tube provided with two sliding seal surfaces, thecoupling becomes very useful as a repair kit for splicing a tee couplinginto an existing uninterrupted thermoplastic pipe. This is done by firstcutting out a section of the thermoplastic pipe along the cut lines asshown in FIG. 5. Next a flange structure, such as 35 and 36, is securedto each end of the exposed facing ends of the cut apart pipe. Then, asshown in FIG. 8, the spring collar 28 is tightly compressed againstflange structure 27 by bolt 29. The give in the spring collar meansurges the sliding seal surface 30 against gasket 31 to form a rotatablepipe coupling. This repair kit provides great flexibility in thethermoplastic plumbing field. Rather than pulling out all the oldplumbing in a particular installation, a rotatable tee" coupling can besimply spliced into the existing pipe line as explained above.

In the above descriptions in the specification l have refered to a sidetube of the rotatable coupling. it is also contemplated that two sidetubes 38 and 39 be used to form a "double sanitary tee. More side tubescould also be used if desired.

l have found that the rotatable pipe coupling of this invention worksvery well when the pipe, flange, and side tube are all integrallyinjection molded of acrylonitrile-butadiene-styrene, (ABS),thermoplastic as a onepiece unit. The spring collar is also injectionmolded of ABS as a one-piece unit. I discovered that this provides arigid pipe coupling with sufficient give in the flange and the springcollar to permit the collar to be snapped over the flange. After thecollar and main tube have been assembled the collar can be tightlysqueezed against an adjacent flange and give" sufficiently so that asliding seal surface of the main tube can be mannually rotated toangularly position the side tube. Thereafter, the side tube is joined toa connecting pipe. in the foregoing specification, l have used specificexamples of my rotatable pipe coupling to describe my invention.However, it is understood that persons skilled in the art can makecertain modifications to these examples without departing from thespirit and scope of the invention.

l claim:

1. A rotatable pipe coupling comprising: a tube with a longitudinal mainpassage and an annular sliding seal surface encircling the passage; anexternal flange and side protuberance on the tube, said sideprotuberance having a side passage therethrough communicating with themain passage of the tube; and an annular spring collar plate having anouter coupling-supporting portion for fixedly securing the coupling to aconnecting structure, said spring collar plate fitting around the tubeand having an annular inner portion permanently retained between theflange and protuberance, and having an annular intermediate portion thatextends radially outwardly beyond the flange, the inner portion of saidspring collar plate and tube having sufficient circumferential clearancetherebetween to prevent circumferential seizing between the collar plateand tube, the inner and intermediate portions of said collar plateforming a unit with a flex section that is longer than it is thick in adirection extending outwardly from the tube and has sufficient inherentresilence to flex in a direction longitudinally along the tube toslidably engage said flange and to urge the sliding seal surface againsta connecting structure to form a sliding joint whereby the tube can bemanually rotated about an axis to angularly position the side passage ofthe tubes side protuberance.

2. The combination as set forth in claim 1, wherein the flange and sideprotuberance are integrally formed with the tube.

3. The combination as set forth in claim 2, wherein the tube, flange,and side protuberance form a onepiece molded thermoplastic unit.

4. The combination as set forth in claim 2, wherein the spring collarplate is a thin thermoplastic plate.

5. The combination as set forth in claim 4, wherein the thermoplasticplate is of acrylonitrile-butadienestyrene, (ABS).

6. The combination as set forth in claim 2, wherein the spring collarplate is a one-piece thermoplastic plate with a circular passage and anannular homogeneous thermoplastic portion which extends uninterruptedaround the opening.

7. The combination as set forth in claim 6, wherein the circular passageof the spring collar plate is substantially smaller than either theflange or side protuberance areas of the tube.

8. The combination as set forth in claim 7, wherein the annular portionof the collar plate has a beveled inner surface defining the circularpassage of the spring collar plate, and the flange is integrally formedwith the tube and has a beveled outer surface, whereby the spring collarplate can be snapped over the flange, so the tube permanently androtatably retains a portion of the spring collar plate between theflange and side protuberance.

9. The combination as set forth in claim 8, wherein the tube, flange,and spring collar plate are of acrylonitrile-butadiene-styrene, (ABS).

10. The combination as set forth in claim 1, wherein the longitudinalmain passage has opposite ends and said side passage of the sideprotuberance intersects the tubes main passage intermediate its oppositeends to form a rotatable tee pipe coupling.

11. The combination as set forth in claim 1, wherein the tube has twoside protuberances, each of which have a passage intersecting the tubespassage to form a rotatable double tee pipe coupling.

12. The combination as set forth in claim 1, wherein the rotatable pipecoupling is connected to a slide gate valve at the sliding seal surface.

13. The combination as set forth in claim 1, wherein the sliding sealsurface is adjacent one end of the tube,

and there is a removable cap fitting over an opposite end of the tube.

14. The combination as set forth in claim 1, wherein there is aresilient gasket between the sliding seal surface and the connectingstructure.

15. The combination as set forth in claim 14, wherein the gasket has anarrow upstanding bead which engages the tubes sliding seal surface.

16. The combination as set forth in claim 15, wherein the narrow annularbead has a generally triangular cross section.

17. The combination as set forth in claim M, wherein the gasket isrubber.

18. The combination as set forth in claim ll, wherein the connectingstructure has an external connecting flange and the spring collar plateis tightly compressed against the connecting flange by bolts or the likeand the tube remains manually rotatable.

19. The combination as set forth in claim 1, wherein the tube has twosliding seal surfaces and two spaced apart flanges 'with the sideprotuberances located be tween these flanges and there is a springcollar plate fitting around the tube between each flange and the sideprotuberance, whereby the coupling can be spliced into a cut out area ofpipe and the side protuberance rotated to a desired angular position.

20. A rotatable pipe coupling comprising: a thermoplastic main tube witha longitudinal passage and with an end sliding seal surface encirclingthis passage; an integral external thermoplastic flange adjacent thesliding seal surface, which flange has an outer beveled surface thatslopes inwardly toward the sliding seal surface; a thermoplastic sidetube integrally connected with the main tube forming a tee; a thinthermoplastic plate of acrylonitrile-butadiene-styrene (ABS) with anopening surrounded by a beveled inner surface smaller in diameter thanthe flanges external surface and fitting between the flange and sidetube, said plate having sufficient give in a direction generallyparallel to the tubes longitudinal passage to provide a liquid tightseal at the sliding seal surface; a connecting pipe structure with aflange, said plate being firmly compressed against this flange by boltsor the like; and a rubber sealing gasket between the connecting pipestructure and the sliding seal surface, which sliding seal surfaceslides against this gasket when the main tube is rotated to angularlyposition the side tube.

21. A rotatable pipe coupling comprising: a thermoplastic main tube witha longitudinal main passage and with an end sliding seal surfaceencircling this passage; an integral external thermoplastic flangeadjacent the sliding seal surface, which flange has an outer beveledsurface that slopes inwardly toward the sliding seal surface; athermoplastic side tube integrally connected with the main tube andhaving a side passage communicating with the main passage; a thinthermoplastic plate with an opening surrounded by a beveled innersurface smaller in diameter than the flanges external surface andfitting between the flange and side tube, said plate having sufficientgive in a direction generally parallel to the tubes longitudinal passageto slidably engage said flange, to urge the tube axially and to providea liquidtight seal at the sliding seal surface; a connecting pipestructure with a flange, said plate being firmly compressed against thisflange by bolts or the like; and a resiliant sealing gasket between theconnecting pipe structure and the sliding seal surface, which slidingseal surface slides against this gasket when the main tube is rotated toangularly position the side tube.

1. A rotatable pipe coupling comprising: a tube with a longitudinal mainpassage and an annular sliding seal surface encircling the passage; anexternal flange and side protuberance on the tube, said sideprotuberance having a side passage therethrough communicating with themain passage of the tube; and an annular spring collar plate having anouter couplingsupporting portion for fixedly securing the coupling to aconnecting structure, said spring collar plate fitting around the tubeand having an annular inner portion permAnently retained between theflange and protuberance, and having an annular intermediate portion thatextends radially outwardly beyond the flange, the inner portion of saidspring collar plate and tube having sufficient circumferential clearancetherebetween to prevent circumferential seizing between the collar plateand tube, the inner and intermediate portions of said collar plateforming a unit with a flex section that is longer than it is thick in adirection extending outwardly from the tube and has sufficient inherentresilence to flex in a direction longitudinally along the tube toslidably engage said flange and to urge the sliding seal surface againsta connecting structure to form a sliding joint whereby the tube can bemanually rotated about an axis to angularly position the side passage ofthe tube''s side protuberance.
 2. The combination as set forth in claim1, wherein the flange and side protuberance are integrally formed withthe tube.
 3. The combination as set forth in claim 2, wherein the tube,flange, and side protuberance form a one-piece molded thermoplasticunit.
 4. The combination as set forth in claim 2, wherein the springcollar plate is a thin thermoplastic plate.
 5. The combination as setforth in claim 4, wherein the thermoplastic plate is ofacrylonitrile-butadiene-styrene, (ABS).
 6. The combination as set forthin claim 2, wherein the spring collar plate is a one-piece thermoplasticplate with a circular passage and an annular homogeneous thermoplasticportion which extends uninterrupted around the opening.
 7. Thecombination as set forth in claim 6, wherein the circular passage of thespring collar plate is substantially smaller than either the flange orside protuberance areas of the tube.
 8. The combination as set forth inclaim 7, wherein the annular portion of the collar plate has a beveledinner surface defining the circular passage of the spring collar plate,and the flange is integrally formed with the tube and has a beveledouter surface, whereby the spring collar plate can be snapped over theflange, so the tube permanently and rotatably retains a portion of thespring collar plate between the flange and side protuberance.
 9. Thecombination as set forth in claim 8, wherein the tube, flange, andspring collar plate are of acrylonitrile-butadiene-styrene, (ABS). 10.The combination as set forth in claim 1, wherein the longitudinal mainpassage has opposite ends and said side passage of the side protuberanceintersects the tube''s main passage intermediate its opposite ends toform a rotatable ''''tee'''' pipe coupling.
 11. The combination as setforth in claim 1, wherein the tube has two side protuberances, each ofwhich have a passage intersecting the tube''s passage to form arotatable ''''double tee'''' pipe coupling.
 12. The combination as setforth in claim 1, wherein the rotatable pipe coupling is connected to aslide gate valve at the sliding seal surface.
 13. The combination as setforth in claim 1, wherein the sliding seal surface is adjacent one endof the tube, and there is a removable cap fitting over an opposite endof the tube.
 14. The combination as set forth in claim 1, wherein thereis a resilient gasket between the sliding seal surface and theconnecting structure.
 15. The combination as set forth in claim 14,wherein the gasket has a narrow upstanding bead which engages thetube''s sliding seal surface.
 16. The combination as set forth in claim15, wherein the narrow annular bead has a generally triangular crosssection.
 17. The combination as set forth in claim 14, wherein thegasket is rubber.
 18. The combination as set forth in claim 1, whereinthe connecting structure has an external connecting flange and thespring collar plate is tightly compressed against the connecting flangeby bolts or the like and the tube remains manually rotatable.
 19. Thecombination as set forth in claim 1, wherein the tube has two slidingseal surfaces and two spaced apart flanges with the side protuberanceslocated between these flanges and there is a spring collar plate fittingaround the tube between each flange and the side protuberance, wherebythe coupling can be spliced into a cut out area of pipe and the sideprotuberance rotated to a desired angular position.
 20. A rotatable pipecoupling comprising: a thermoplastic main tube with a longitudinalpassage and with an end sliding seal surface encircling this passage; anintegral external thermoplastic flange adjacent the sliding sealsurface, which flange has an outer beveled surface that slopes inwardlytoward the sliding seal surface; a thermoplastic side tube integrallyconnected with the main tube forming a ''''tee''''; a thin thermoplasticplate of acrylonitrile-butadiene-styrene (ABS) with an openingsurrounded by a beveled inner surface smaller in diameter than theflange''s external surface and fitting between the flange and side tube,said plate having sufficient ''''give'''' in a direction generallyparallel to the tube''s longitudinal passage to provide a liquid tightseal at the sliding seal surface; a connecting pipe structure with aflange, said plate being firmly compressed against this flange by boltsor the like; and a rubber sealing gasket between the connecting pipestructure and the sliding seal surface, which sliding seal surfaceslides against this gasket when the main tube is rotated to angularlyposition the side tube.
 21. A rotatable pipe coupling comprising: athermoplastic main tube with a longitudinal main passage and with an endsliding seal surface encircling this passage; an integral externalthermoplastic flange adjacent the sliding seal surface, which flange hasan outer beveled surface that slopes inwardly toward the sliding sealsurface; a thermoplastic side tube integrally connected with the maintube and having a side passage communicating with the main passage; athin thermoplastic plate with an opening surrounded by a beveled innersurface smaller in diameter than the flange''s external surface andfitting between the flange and side tube, said plate having sufficient''''give'''' in a direction generally parallel to the tube''slongitudinal passage to slidably engage said flange, to urge the tubeaxially and to provide a liquid tight seal at the sliding seal surface;a connecting pipe structure with a flange, said plate being firmlycompressed against this flange by bolts or the like; and a resiliantsealing gasket between the connecting pipe structure and the slidingseal surface, which sliding seal surface slides against this gasket whenthe main tube is rotated to angularly position the side tube.